This competitive renewal application requests continuation of core support for the Rochester Epidemiology Project (REP), the medical record linkage system for health care providers to residents of Olmsted County, Minnesota. This unique data resource chronicles the medical care delivered to community residents from the early 1900's to the present and has supported population-based epidemiologic investigations of virtually every study design and of most disease entities occurring in this country. The REP has supported the work of a large number of investigators at Mayo Clinic and other academic institutions permitted the efficient conduct of extramurally-supported studies of conditions with substantial societal impact, including 25 R01 and other research grants, 6 program project/center grants and 17 fellowship/training grants. Since first funded 40 years ago, more than 1,500 manuscripts based on the REP have been published in the peer-reviewed literature, including 351 since our last competitive renewal four years ago These extensive data from a geographically-defined population are virtually unparalleled in this country, and it is essential that this important research resource be preserved and continually updated. Each cycle of this grant has presented an opportunity to not only maintain the core record linkage function, but to enhance its utility as well. For our next project cycle, we propose to update the data resources through the continued enumeration of the population of Olmsted County and linking them with medical events (Aim 1); collate information that can be used to augment genetic studies such as the existence of archived biologic specimens, distributions of genetic polymorphisms and birth certificate information (Aim 2) and enhancing data security and improving logistical support for end-users of the REP (Aim 3). This builds on our accomplishments from the previous funding period that include better timeliness of data collection, addition of new sources of information, and development of tools to increase ease of access while providing greater data security. Thus, the efforts planned for this next funding cycle will provide increased data availability for the growing pool of clinical investigators who, in conjunction with multidisciplinary teams of epidemiologists, statisticians and basic scientists, are exploiting the new sciences to address significant questions with a goal of translating findings into improved medical practice and better health for the population as outlined in the NIH Road Map.